cmux-tui-core: a new release stamp no longer recompiles cmux-tui-core

cmux-tui/crates/cmux-tui-core/src/release.rs

@@ -9,10 +9,27 @@ use std::path::{Component, Path};
 /// test build, or a raw R2 tree artifact stamped `0.0.0-r2.sha-…` that the
 /// app bundles) reports the one cmux-next version, the workspace crate
 /// version, which `scripts/cmux-next/check-version-surfaces.sh` requires.
-pub const DISTRIBUTION_VERSION: &str = match option_env!("CMUX_TUI_DISTRIBUTION_VERSION") {
-    Some(version) if is_release(version) => version,
-    _ => env!("CARGO_PKG_VERSION"),
-};
+/// The binary stamps it (`CMUX_TUI_DISTRIBUTION_VERSION`) and installs it at
+/// start ([`install_distribution_version`]), so a new stamp (every build of
+/// the Linux pool) recompiles the binary and not this crate.
+pub fn distribution_version() -> &'static str {
+    INSTALLED_DISTRIBUTION_VERSION.get().copied().unwrap_or(env!("CARGO_PKG_VERSION"))
+}
+
+static INSTALLED_DISTRIBUTION_VERSION: std::sync::OnceLock<&'static str> =
+    std::sync::OnceLock::new();
+
+/// Records the binary's stamped release, `None` when it has none. A placeholder
+/// stamp is not a release ([`is_release`]). The first call wins.
+pub fn install_distribution_version(stamped: Option<&'static str>) {
+    let _ = INSTALLED_DISTRIBUTION_VERSION.set(release_or_workspace(stamped));
+}
+
+/// A release stamp as the version to report: the workspace crate version for
+/// none or a placeholder.
+fn release_or_workspace(stamped: Option<&str>) -> &str {
+    stamped.filter(|version| is_release(version)).unwrap_or(env!("CARGO_PKG_VERSION"))
+}
 
 /// A release version: not empty and not a `0.0.0-…` placeholder stamp.
 pub const fn is_release(version: &str) -> bool {
@@ -127,3 +144,18 @@ pub fn update_hint_for(install: Option<&str>) -> String {
         ),
     }
 }
+
+#[cfg(test)]
+mod distribution_tests {
+    /// What the binary installs is what `DISTRIBUTION_VERSION` was when this
+    /// crate read the stamp itself: a release as stamped, anything else the
+    /// workspace crate version.
+    #[test]
+    fn only_a_release_stamp_is_reported_as_the_release() {
+        use super::release_or_workspace;
+        assert_eq!(release_or_workspace(Some("0.13.4")), "0.13.4");
+        assert_eq!(release_or_workspace(Some("0.0.0-r2.sha-abc")), env!("CARGO_PKG_VERSION"));
+        assert_eq!(release_or_workspace(Some("")), env!("CARGO_PKG_VERSION"));
+        assert_eq!(release_or_workspace(None), env!("CARGO_PKG_VERSION"));
+    }
+}

cmux-tui/crates/cmux-tui-core/src/server/agent_session_proxy.rs

@@ -140,7 +140,7 @@ pub(super) fn bind(
         writer,
         id,
         json!({"app": "cmux-tui", "protocol": super::super::PROTOCOL_VERSION,
-        "version": crate::release::DISTRIBUTION_VERSION, "generation": mux.registry_identity().1,
+        "version": crate::release::distribution_version(), "generation": mux.registry_identity().1,
         "capabilities": ["agent-session-attach-v1", "agent-session-observe-v1"]}),
     )
 }

cmux-tui/crates/cmux-tui-core/src/server/api_revision_wire.rs

@@ -67,7 +67,7 @@ pub(super) fn too_old_text(why: &str, version: Option<&str>, install: Option<&st
     let release = version.map_or_else(String::new, |version| format!(" (cmux {version})"));
     format!(
         "this client{release} is too old for this cmux-tui daemon (cmux {}): {why}. To fix it, {}",
-        crate::release::DISTRIBUTION_VERSION,
+        crate::release::distribution_version(),
         crate::release::update_hint_for(install)
     )
 }

cmux-tui/crates/cmux-tui-core/src/server/api_revision_wire_tests.rs

@@ -129,7 +129,7 @@ fn api_revision_too_old_refusal_names_the_clients_update_command() {
     );
 
     let identity = run(json!({"cmd":"identify","revisions":true})).unwrap();
-    assert_eq!(identity["version"], crate::release::DISTRIBUTION_VERSION);
+    assert_eq!(identity["version"], crate::release::distribution_version());
     assert!(identity["install"].is_string());
     mux.shutdown();
 }

cmux-tui/crates/cmux-tui-core/src/server/cmd_server.rs

@@ -44,7 +44,7 @@ pub(super) fn identify(
     let mut identity = json!({
         "app": "cmux-tui",
         // The npm/PyPI release (the crate version in the app and local builds).
-        "version": crate::release::DISTRIBUTION_VERSION,
+        "version": crate::release::distribution_version(),
         "build_commit": stamped_build_commit(),
         "build_id": build_id,
         "cli_path": cli_path,

cmux-tui/crates/cmux-tui/src/main.rs

@@ -1710,6 +1710,7 @@ pub fn main() -> std::process::ExitCode {
     unsafe { startup_env::take_link_token_from_env() };
     // Before any mode can serve `identify` or `ping`.
     cmux_tui_core::server::install_build_stamp(build_stamp());
+    cmux_tui_core::release::install_distribution_version(version_report::DISTRIBUTION_STAMP);
     // `cmux` (CLI and mux) and `acpmux` (a symlink) are one binary, one version.
     #[cfg(unix)]
     if std::env::args_os()

cmux-tui/crates/cmux-tui/src/session/remote.rs

@@ -166,7 +166,8 @@ fn validate_remote_identity(ident: &Value) -> anyhow::Result<()> {
 /// The refusal for a version skew, naming the exact update command of the
 /// side that is too old (plans/cmux-next/tui-tester-rollout.md #4).
 fn skew_refusal(ident: &Value, protocol: u64, client_too_old: bool) -> String {
-    use cmux_tui_core::release::{DISTRIBUTION_VERSION, InstallChannel, update_hint_for};
+    use crate::version_report::{DISTRIBUTION_VERSION, InstallChannel};
+    use cmux_tui_core::release::update_hint_for;
     let server = ident.get("version").and_then(Value::as_str).unwrap_or("unknown");
     if client_too_old {
         format!(

cmux-tui/crates/cmux-tui/src/session/remote/connect.rs

@@ -185,7 +185,7 @@ impl RemoteSession {
         // how we were installed, so it can translate for us or name our
         // update command when it refuses (server/api_revision_wire.rs).
         if ident.get("api_revision").is_some() {
-            use cmux_tui_core::release::{DISTRIBUTION_VERSION, InstallChannel};
+            use crate::version_report::{DISTRIBUTION_VERSION, InstallChannel};
             client_info.set(
                 "api_revision",
                 json!(

cmux-tui/crates/cmux-tui/src/version_report.rs

@@ -8,12 +8,24 @@
 
 use std::path::Path;
 
+pub(crate) use cmux_tui_core::release::InstallChannel;
 use cmux_tui_core::release::is_release;
-pub(crate) use cmux_tui_core::release::{DISTRIBUTION_VERSION, InstallChannel};
+
+/// This binary's release stamp, `None` for a build that has none. Read only
+/// here: cmux-tui-core gets it at start (`install_distribution_version`), so a
+/// new stamp recompiles this crate and not the libraries.
+pub(crate) const DISTRIBUTION_STAMP: Option<&str> = option_env!("CMUX_TUI_DISTRIBUTION_VERSION");
+
+/// The npm/PyPI release that contains this binary, as
+/// `cmux_tui_core::release::distribution_version` reports it once installed.
+pub(crate) const DISTRIBUTION_VERSION: &str = match DISTRIBUTION_STAMP {
+    Some(version) if is_release(version) => version,
+    _ => env!("CARGO_PKG_VERSION"),
+};
 
 /// Whether this binary was stamped as an npm/PyPI release (not a `0.0.0-…`
 /// placeholder): crash forwarding and the update check run only then.
-pub(crate) const RELEASE_STAMPED: bool = match option_env!("CMUX_TUI_DISTRIBUTION_VERSION") {
+pub(crate) const RELEASE_STAMPED: bool = match DISTRIBUTION_STAMP {
     Some(version) => is_release(version),
     None => false,
 };